Objective To knock down angiopoietin-1 expression in human gastric cancer cell line BGC-823 and to observe its effect of reversing tumor invasion. Methods siRNA sequence fragments was designed to target angiopoietin-1 and transferred into human gastric cancer cell line BGC-823. RT-PCR was used to assess the transcription level of angio-poietin-1 mRNA, then western blot and immunofluorescence were used to examine the expression level of three invasion-as-sociated proteins include integrinβ1, CD44V6 and Ang-1. Cell adhesion ability was evaluated by cell adhesion assay and cell invation was determined by matrigel and transwell plastic dual-chamber culture system. Results Ang-1 mRNA was knocked down by siRNA showed by RT-PCR. The expression of integrinβ1, CD44V6 and Ang-1 were significantly lower than control group(P<0.05), so did the cellular adhesion and invasion abilities(P<0.05). Conclusion Knocking down angiopoietin-1 by siRNA can reverse invasion of human gastric cancer cell line BGC-823 and may provide new ideas and reference for gene therapy of gastric cancer in the future.

Objective To investigate the effectiveness and safety of endoscopic mucosal resection with precutting(EMR-P)for the treatment of rectal neuroendocrine neoplasm(RNEN)smaller than 1 cm in diameter.Methods Clinical data of 177 patients with RNEN smaller than 1 cm in diameter from December 2016 to December 2021 were retrospectively analyzed.According to different treatment protocols,177 patients with RNEN were divided into endoscopic mucosal resection(EMR)group(n = 46),EMR-P group(n = 40)and endoscopic submucosal dissection(ESD)group(n = 91).The en bloc resection rate,complete resection rate,operation time,postoperative hospitalization time and incidence of operative complications among the three groups were compared.Results The complete resection rate in the EMR-P group(95.0%)and ESD group(97.8%)were significantly higher than that in the EMR group(87.0%)(P<0.05);The operation time in the EMR-P group(9.86±2.23)min was longer than that in the EMR group(4.12±0.88)min,EMR-P group and EMR group were shorter than that in the ESD group(19.55±3.67)min,the difference was statistically significant(P<0.05);Postoperative hospitalization time in the EMR group was(2.45±0.29)d and EMR-P group was(2.43±0.23)d,which were shorter than that in the ESD group(3.30±0.32)d,and the difference was statistically significant(P<0.05).There were no significant difference in the rates of en bloc resection and operative complications among the three groups(P>0.05).Conclusion EMR-P for the treatment of RNEN<1 cm in diameter has the advantages,such as simple operation,short operation time and hospitalization time,high histological complete resection rate and low complication rate,which is worthy of clinical application.